Silverware burnishing is a process that combines surface hardening and polishing without the use of abrasives. On a microscopic scale, a metal surface is actually composed of tightly packed individual ‘grains’. The basic theory of burnishing is that these surfaces can be hardened and shined through the manipulation of these grains.
Over time and normal use, silverware is scratched and tarnished with a thin residue of silver sulfide. This results in reducing the polished surface finish and texture. The burnishing process is designed to restore the silver surface through a barrel tumbling process. This process forces the metal to ‘flow’ and physically fill the scratches. At the same time, the burnishing process chemically removes the tarnish.
This combination of chemical cleaning and physical compaction results in a shiny, hardened surface that improves the surface appearance and increases the lifetime of the silverware.